Block #366,150

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/19/2014, 5:48:00 AM · Difficulty 10.4266 · 6,437,411 confirmations

2CC
Cunningham Chain of the Second Kind

A sequence where each prime is double the previous prime minus one.

Block Header
Block Hash
d1b83d5c176bedda47d0564af118a57d6f9a3bbfd364288a0dc8c0aa4b342c6d

Height

#366,150

Difficulty

10.426578

Transactions

8

Size

14.03 KB

Version

2

Bits

0a6d343d

Nonce

81,833

Timestamp

1/19/2014, 5:48:00 AM

Confirmations

6,437,411

Merkle Root

520008f6a7d6521502226ea29d0fd5d49b5e25f62ecf8a1a7f8d454f6c3f8f80
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

9.723 × 10⁹⁵(96-digit number)
97232298256541377892…52224337654876233601
Discovered Prime Numbers
p_k = 2^k × origin + 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

1
origin + 1
9.723 × 10⁹⁵(96-digit number)
97232298256541377892…52224337654876233601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.944 × 10⁹⁶(97-digit number)
19446459651308275578…04448675309752467201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.889 × 10⁹⁶(97-digit number)
38892919302616551157…08897350619504934401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
7.778 × 10⁹⁶(97-digit number)
77785838605233102314…17794701239009868801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.555 × 10⁹⁷(98-digit number)
15557167721046620462…35589402478019737601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.111 × 10⁹⁷(98-digit number)
31114335442093240925…71178804956039475201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
6.222 × 10⁹⁷(98-digit number)
62228670884186481851…42357609912078950401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.244 × 10⁹⁸(99-digit number)
12445734176837296370…84715219824157900801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.489 × 10⁹⁸(99-digit number)
24891468353674592740…69430439648315801601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.978 × 10⁹⁸(99-digit number)
49782936707349185481…38860879296631603201
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Cunningham Chain of the Second Kind. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

★★☆☆☆
Rarity
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,672,520 XPM·at block #6,803,560 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.